The KA630-A CPU modules were used in MicroVAX II systems, KA630-B's
can be found in VAXstation II and VAXstation II/GPX machines. As you can
see on the two pictures above, two PCB layouts were used: KA630-based systems
shipped after 1st of February, 1987 are likely to contain the newer M7606
A1 revision. There are no functional differences between the cards. The
difference between the KA630-AA and a KA630-AB is that the -AB doesn't
contain the hardare floating point unit, instead, these instructions are
supported through software emulation. The VAXstation is a MicroVAX II with
a QVSS graphics module (VCB01), the VAXstation II/GPX is a a MicroVAX II
with the QDSS (VCB02) graphics board-set. Both are one-user systems from
the operating system side by default.

The KA630 CPU features LMI (Local Memory Interconnect), which uses three
different paths to system memory: the qbus, the C-D interconnect of the
backplane (thus it must be fitted into a Q22/CD backplane, which is usually
a BA23 or BA123 enclosure
with a "mixed" backplane), and a ribbon cable
that connects the CPU module to MS630 or compatible third-party memory
boards. This means, that you can use qbus memory cards in a MicroVAX II
(although it results in weaker performance), or you can use LMI MicroVAX
II memory modules. Do not try to use LMI memory modules intended for later
MicroVAX systems (modules like the MS650-series, etc)! The CPU module should
go into the first slot of the backplane, the LMI memory boards should be
next (don't stuff more than 16 MBs of memory onto the bus, it won't work;
don't insert MicroVAX II LMI memory modules into Q22/Q22 slots either).

The KA630 features:

MicroVAX chip

FPP (optional, but I haven't seen one without it, of course this means
only that I haven't seen enough M7606 modules)

Upon powering, the CPU enters one of the three boot-up modes, which
can be selected on the CPU Patch Panel. Then, it
determines the console type and language (if the boot-up switch on the
CPU Patch Panel is in the "Language Query" state, the system asks for the
language to use in console mode. This (and other parameters too) is stored
in battery backed-up memory. If the battery (which is on the back side
of the Patch Panel) is dead, these parameters are lost, and must be entered
upon power-up). It displays the "Performing normal system tests." message
(in the selected language that is), and a countdown is displayed.

KA630-A.01

Performing normal system tests.

7.. 6.. 5.. 4.. 3..

Tests completed.

Now, depending on the state of the "halt enable" switch on the CPU Patch
Panel, the console prompt (">>>", also called the "chevron") is displayed
(if halt is enabled), or the system attempts to boot (if halt is disabled).
The boostrap is searching for a bootable device in the following sequence:
1. MSCP disks (disk controller at 17772150 or at a floating CSR), named
DUxy, DAxy, DJxy (fixed disk, floppy)
2. TMSCP tape drive at 17774500 or at a floating CSR, named MUxy (for
example a TK50 drive)
3. boot PROM (for example on an MRC11 module)
4. Ethernet adapter at 17774440 or 17774460, named XQAx or XQBx

A successful bootstrap looks like this:

2.. 1..

-DUA0

0...

Loading system software.

This countdown is also displayed on the LEDs of the Patch Panel and on
LEDs on the CPU module.

If there's nothing on the console display, nor on the bulkhead LED display,
check if the CPU's in place, check the cable from the CPU module to the
bulkhead panel. I've experienced some silly behaviour when using too long
ribbon cables between the CPU and the Patch Panel... I you cannot use the
computer, as it loops theough the tests, check if the power-on mode switch
on the Patch panel is in the "test loop" position.
If you get the "Normal operation not possible" message on a VAXstation
II (with a graphics board) using the Patch Panel console port, don't worry,
it might be normal: the CPU wants to use the video board for console in
this case. You cannot run graphics on the console serial port, but apart
from that, the system should work.

The CPU Patch Panel Insert

Picture 3: The CPU Patch Panel, sometimes called the
"bulkhead"

The two-position switch is for halt enable/disable ("dot in circle"
is enabled).
The LED display is for displaying the power-up test countdown
The three-position rotary switch is for selecting power-up modes ("arrow":
normal operation", "face": language inquery mode, "T in circle": test loop
mode)
The eight-position rotary switch is for selecting the baud rate for
the console terminal (from 300 baud to 38400)

The console port

The male DB9 connector is for the console. It's not a 9-pin PC serial
port! You must have a Digital BCC08 cable, or build one. The
pinout is:

This is in general a null modem cable (pins 2-3, 3-2, 7-7, with the 8th
and 9th pin on the VAX-side shorted; speaking from experience, you don't
need all the pins that are connected in the BCC08 cable).

Console commands

The KA630 has two operating states. One is normal operation (programmed
I/O), the other is console I/O. Console I/O is entered when the
"Halt enable/disable" switch on the CPU Patch
Panel is in the enable position and a/ the "Halt" button on
the system control panel is pressed b/ upon power-up. You are also dropped
into console mode, when something fatal occurs to the operating system.
You can identify the console state from the "chevron" prompt:

>>>

You can enter bootstrap/diagnostic commands form this prompt (e.g. you
can play around with memory locations, registers, etc).
The most important commands:

BOOT </qualifier> [DEVICE]Boots the specified device (DUxy for disks where x
is the controller number, y is the disk on that controller, MUxy
for TMSCP tapes (in the same manner) XQA0 or XQB0 for Ethernet).
If no device is pecified, the system goes through the sequence discussed
at power-up tests. Qualifier: /R5:<value>
- the <value> gets passed to VMB (primary boot loader).

CONTINUEThe CPU starts instruction execution from the address in the PC (Program
Counter). No initialization is performed.

0B CHM TO ISTK The exception vector for a change mode had
bit <0> set.

0C SCB RD ERR A hard memory error occurred while the processor was
trying to read an exception or interrupt vector.

10 MCHK AV An access violation or an invalid translation

11 KSP AV An access violation or an invalid translation
occurred during processing of an invalid kernel
stack pointer exception.

15 CORRPTN The console database was corrupted. The console
program simulates a power-up sequence and
rebuilds its database.

16 ILL REF The requested reference would violate virtual
memory protection, the address is not mapped,
the reference is invalid in the specified
address space, or the value is invalid in the
specified destination.

17 ILL CMD The command string cannot be parsed.

18 INV DGT A number has an invalid digit.

19 LTL The command was to large for the console to
buffer. The message is issued only after receipt
of the terminating carriage return.

1C SW CONF For example, two different data sizes are
specified with an EXAMINE command.

1D UNK SW The switch is unrecognized.

1E UNK SYM The symbolic address in an EXAMINE or DEPOSIT
is unrecognized.

1F CHKSM The command or data checksum of an X command
is incorrect. If the data checksum is
incorrect, this message is issued and is not
abbreviated to "Illegal Command".
occurred during machine check exception
processing.

20 HLTED The operator entered a HALT command.

21 FND ERR A FIND command failed either to find the RPB or
64 kb of good memory.

22 TMOUT During an X command, data failed to arrive in
the time expected.